Dereferencing Strings

[CapnNickSparrow]

Hello there, so in the beginning of the courses you told us to use the * before HiddenWord, which I did but I did not understand the pointer stuff of it. Now we use it again, which is fine, but unlike the rest of what you explain to me I have no idea what, why, when this works. I miss the whole explanation of this and it is bothering me a lot since I had such a problem before and I am doing this course but my way so I make something more unique but I find this essential in understanding.

[DanM]

Does my answer here help at all?

Confusion about pointers in this lesson

To avoid possible confusion *HiddenWord this does not make HiddenWord a pointer or get it’s address. FString has overloaded the dereference operator to do something different here. FString is a class created by Epic and stores a TArray of TCHAR (correct char type for Unicode depending on platform). These chars are stored next to each other in memory and null terminated. FString::Printf uses one of the printf family of functions from C. C deals with strings by a pointer to the first element of…

[CapnNickSparrow]

I guess so, so I short because we use a combination of C and Unreal stuff the variable needs to be converted so it will be understood, the * makes sure of it. If we used it another way it did not had to be done but in this case the code just doesn’t know the content of the variable, so we use a dereference converter basically to extract that information out of it? Sounds like a crappy explanation, but hope you understand, is this correct?

[DanM]

@CapnNickSparrow

because we use a combination of C and Unreal stuff

Unreal is using C and uses it in its API.

@CapnNickSparrow

If we used it another way it did not had to be done but in this case the code just doesn’t know the content of the variable, so we use a dereference converter basically to extract that information out of it?

Basically, yes. A very oversimplified version is that FString looks a little something like this

class FString
{
public:
    const TCHAR* operator*() const 
    {
        if (IsEmpty())
        {
            return TEXT("");        
        }
        return Data;
    }
    bool IsEmpty() const { return Size == 0; }
private:
    TCHAR* Data;
    int32 Size;
};